Office of Compensation Analysis and Support 

Program Evaluation Report

Document Number: OCAS-PER-007

Effective Date: 11/09/2006 

Revision No. 0

Evaluation of the Effect of Revision 2 of the Site Profile on Previously 

Completed Bethlehem Steel Cases 

Page 1 of 7 

Author: Signature on file Date: 11/14/2006 Dave Allen, HP Team Leader 

Approval: : Signature on file Date: 11/14/2006 

 J.W. Neton, Associate Director for Science 

Supersedes: None 

RECORD OF ISSUE/REVISIONS 

ISSUE 

AUTHORIZATION 

DATE 

11/14/2006

EFFECTIVE 

DATE 

11/14/2006 

REV. NO. 

0 

DESCRIPTION 

New document to evaluate the effect of revision 2 

of the site profile on previously completed dose 

reconstructions from Bethlehem Steel 

1.0 Description

On July 27, 2006, OCAS issued a revision to the Bethlehem Steel Corporation Technical 

Basis Document. The changes in this revision were based on the resolution of review 

comments made by Sanford Cohen & Associates, the contractor that supports the 

Advisory Board on Radiation and Worker Health (ABRWH). The significant changes 

made to the site profile include: 

1. The air concentration values were reevaluated using the additional air samples 

that became available after the publication of revision 0. As a result, an era 

specific log-normal distribution of air samples was developed that replaced the 

previous single triangular distribution that was applied to all years of operation. 

Further, NIOSH selected the 95th percentile air concentration of these 

distributions as being representative of the exposure for all claimants. 

2. In 1952, when air concentrations were no longer bounded by rolling operations, 

NIOSH selected the highest recorded air sample, which was taken during a 

grinding operation, as representative of the breathing zone concentration for all 

workers. 

3. An exposure scenario for the torch cutting of uranium cobbles was added. 

4. The uranium ingestion model was revised to better reflect the air concentration 

and contamination conditions that existed at BSC. 
Office of Compensation Analysis and Support

Program Evaluation Report Document Number: OCAS-PER-007

Effective Date: (11/14/2006) Revision No. 0 Page 2 of 7 

5. The resuspension model was revised to increase the plausible bounding value for 

exposure from this pathway, 

6. The external exposure model was revised to allow for exposure to contaminated 

clothing for up to two weeks between washings. This increased the shallow dose 

to the skin to1.8 rem per year from potential uranium contamination on clothing. 

The purpose of this PER is to evaluate the magnitude of the effect these changes made on 

the probability of causation for previously reconstructed cases. That is, all cases 

reconstructed using the previous version of the site technical basis document were 

evaluated to determine if the magnitude of the change in dose is sufficient to move the 

probability of causation (PC) to greater than or equal to 50% at the 99% credibility 

interval. For completeness, NIOSH also evaluated if any cases that were previously 

found to be greater than 50% would now be less than 50 % when the new models were 

applied. 

As of the approval date for this PER, a total of 579 dose reconstructions for Bethlehem 

Steel have been completed and forwarded to the Department of Labor for adjudication. 

The distribution of the probabilities of causation for these cases is provided in 

Attachment 1. As described below, the approach taken in this evaluation did not rework 

the dose reconstruction for each of the 579 cases. Rather, a methodology was employed 

that identified the cases which were potentially affected by the changes in the TBD. For 

these cases, a full evaluation, including a new IREP analysis, was completed. 

2.0 Issue Evaluation

Comparison of different revisions 

The previous version of the Bethlehem Steel Technical Basis Document (TBD) estimated 

annual internal exposure to uranium by assuming the same inhalation intake for each year 

of employment during the covered period. In the revised version, the intake 

assumptions were divided into three distinct periods. Further, the intakes are assigned as 

a constant value, rather than the triangular distribution that was used in the previous 

revision. When the new constant values are compared to the median value of the 

triangular distribution, the assumed intakes are higher for the first two years of covered 

period and lower for the last two year. Also, the inhalation intake was divided into two 

types of workers, cobble cutters and all others. The intakes assigned to cobble cutters are 

higher than all others for the last two years of operation (1951 and 1952), but lower for 

the first two years. If someone was exposed the entire four years, the non-cobble cutting 

exposure is bounding. The change to internal dose is the primary change for all organs 

other than those that are surficially exposed to shallow dose (i.e., skin, testes and breast) 
Office of Compensation Analysis and Support

Program Evaluation Report Document Number: OCAS-PER-007

Effective Date: (11/14/2006) Revision No. 0 Page 3 of 7 

The shallow dose assumptions were changed to include external shallow dose from 

residual contamination as well as from contaminated clothing. These two sources of 

exposure are modeled as a constant value for each year of covered work. The new values 

are 1.78 rem/yr from residual contamination and 1.80 rem/yr from contaminated clothing. 

This is added to the triangular distribution that was previously included. This is the 

primary change in the estimated dose for the skin, the testes and the breast. 

The remaining changes to the TBD produce only small effects compared to these 

changes. Therefore, assuming that the more substantial changes were responsible for all 

the dose for a given case will overestimate the change in dose. This estimate of the 

change in dose has been used to determine a pool of cases in which the Probability of 

Causation (PC) could change from less than 50% to greater than 50% or visa versa. This 

pool of claims has been further evaluated by performing a dose estimate using revision 2 

of the TBD. 

Probability of Causation 

The dose estimate is used to determine the Excess Relative Risk (ERR). The probability 

of Causation (PC) is determined directly from the ERR. The relationship is: 

PC = ERR/(1+ERR)*100% 

From this equation it can be seen that an ERR of 1 is required to yield a PC of 50%. For 

a given scenario of time since exposure, age at diagnosis, type of cancer, type of 

radiation, etc., the ERR varies essentially linearly with the dose. Therefore, it is possible 

to assess the change in PC on a particular case if the change in dose is known and it is the 

same for all sources of dose. This, of course, is not exactly the case for the changes made 

in the TBD. Only one component of the dose (such as internal dose) will change. 

Therefore, in this evaluation, the changes will be assessed as if the primary source of 

exposure to an individual organ was the only source of exposure. This will overestimate 

the magnitude of the change and produce a larger than necessary group of claims to 

evaluate further. For the purposes of selecting cases for detailed analysis, four categories 

of cases were evaluated. 

Category 1

The first category included cases that reconstructed the dose to organs in which the 

primary dose is from external shallow radiation. This includes skin cancer, as well as 

cancers of the breast and testes. In revision 2, the dose from contaminated clothing and 

from residual contamination was added to the median dose from the shallow dose 

triangular distribution. This newly added dose, was compared to the median dose from 

the previous triangular distribution in revision 0 of the TBD. Based on this comparison, 

it was determined that an original PC of 36.52% would now result in a PC of 50% (if all

the dose for a claim was due to shallow dose). All claims with a skin, testicular or breast 
Office of Compensation Analysis and Support

Program Evaluation Report Document Number: OCAS-PER-007

Effective Date: (11/14/2006) Revision No. 0 Page 4 of 7 

cancer that were previously determined to be <50% PC were reviewed and the ones with 

a PC >30% were selected for further evaluation. This resulted in a pool of 3 claims. 

Category 2

The second category included cases that worked the entire four year period and had organ 

doses that were primarily due to internal irradiation. To facilitate this comparison, the 

median internal dose was calculated for someone working during the entire covered 

period using the exposure scenarios described in revisions 0 and 2. Under revision 2, the 

non-cobble cutter intake was found to result in the largest overall increase in dose. The 

difference in annual organ doses for non-cobble cutters was found to be largest for the 

first two years then dropped significantly. This is due to the fact that the intakes in 

revision 2 are higher than revision 0 only for the first two years. It was decided to use the 

total dose for the first four years as a tool to select cases for further evaluation. This 

should give a conservatively high difference in doses without being so high that all cases 

are re-evaluated. Because the doses drop during the second two years, this was not a 

sufficient selection criterion for people with employment for only part of the covered 

period. These people were assessed with the additional criteria identified under category 

3 below. Using the comparison of the four year total median dose for the most affected 

organ (the liver), it was determined that a PC as low as 41.49% could now result in a PC 

of 50%. Based on this selection criterion, all cases between 40% and 50% were selected 

for further evaluation. This resulted in 8 cases to be further evaluated. 

Category 3

The third category evaluated claims in which employment ended prior to the end of the 

covered period. Since the newest revision results in intakes that are higher in the early 

period and lower in the later periods, it is possible that the second criteria above would 

underestimate the change to a person who worked primarily in the early period. The 

largest change to intakes would occur if the person worked entirely in the first two year 

of the covered period. In that case, a PC as low as 37.58% could now result in a PC of 

50%. All cases with employment ending prior to the end of the four year covered period 

were reviewed for this criterion. Only one of these cases had an original PC greater than 

30% and that case was a skin cancer already selected as part of the first selection 

category. Therefore, this category added no new cases for further evolution. 

Category 4

The fourth category results from the fact that revision 2 results in a lower intakes in the 

last two years than the first two revisions. Therefore, it is possible for someone with a 

PC originally >50% to now be <50%. To assess this, the non-cobble cutting intakes were 

evaluated against the median intakes from the first revision. The original ERR was 

computed based on the original PC and the ERR was reduced by a percentage equal to 
Office of Compensation Analysis and Support

Program Evaluation Report Document Number: OCAS-PER-007

Effective Date: (11/14/2006) Revision No. 0 Page 5 of 7 

the reduction in inhalation intakes for the individual case. As with the other criteria, this 

produced a pool of claims for further evaluation. This criterion resulted in 9 claims to be 

further evaluated. 

3.0 Probability of Causation Evaluation

The 22 cases selected above were re-evaluated by completing a new dose estimate for 

each of the claims. These dose estimates were performed in accordance with revision 2 

of the TBD. The evaluation criteria above were intended to be conservative in order to 

obtain a pool of claims that could potentially change compensability. Therefore, it 

should be expected that not all of these claims will actually change compensability once 

the actual estimate of the dose is completed. The results of the new estimates are 

provided below. In accordance with OCAS practice, any case with a PC greater than 

45% is reported as the average value of 30 IREP iterations using 10,000 trials. Since 

designating the employee as a cobble cutter could increase the PC if employment was not 

for the entire four years, cases in which this may have an affect were evaluated as both a 

cobble cutter and a non-cobble cutter. 

Table 1 - New Estimate for cases from First Criteria 

Case Original PC New PC 

OCAS-PER-007-001 35.46% 48.11% 

OCAS-PER-007-002 34.50% a 43.90% a 

OCAS-PER-007-003 32.56% 41.47% 

a = combination of all cancers 

Table 2 - New Estimate for cases from Second Criteria 

Case Original PC New PC 

OCAS-PER-007-004 43.54% 48.56% 

OCAS-PER-007-005 44.90% 21.65% (38.78% b) 

OCAS-PER-007-006 46.36% 48.54% 

OCAS-PER-007-007 42.06% a 44.08% a 

OCAS-PER-007-008 48.04% a 53.04% a 

OCAS-PER-007-009 47.53% 27.42% 

OCAS-PER-007-010 42.49% a 54.57% a 

OCAS-PER-007-011 43.86% 50.08% 

a = combination of all cancers 

b = PC if employee is assumed to be a cobble cutter 

Table 3 - New Estimate for cases from Fourth Criteria 

Case Original PC New PC 

OCAS-PER-007-012 51.30% 48.82% 
Office of Compensation Analysis and Support

Program Evaluation Report Document Number: OCAS-PER-007

Effective Date: (11/14/2006) Revision No. 0 Page 6 of 7 

OCAS-PER-007-013 52.34% 47.30% 

OCAS-PER-007-014 61.79% 28.27% 

OCAS-PER-007-015 80.05% 55.08% 

OCAS-PER-007-016 74.22% 38.33% (72.33% b) 

OCAS-PER-007-017 64.46% 35.97% 

OCAS-PER-007-018 51.74% 20.39% 

OCAS-PER-007-019 51.73% 20.87% a 

OCAS-PER-007-020 51.50% a 46.02% a 

a = combination of all cancers 

b = PC if employee is assumed to be a cobble cutter 

4.0 Conclusions

As a result of revisions to the Bethlehem Steel TBD, three claims that were previously 

determined to have a PC of less than 50% would now have a PC greater than 50% (Table 

1 and Table 2 above). One of these three cases, however, has new ICD 9 code 

information that the Department of Labor evaluated upon appeal by the claimant. If the 

new ICD code designation is adopted by the DOL, this claim would have a revised PC of 

less than 50%. The specific circumstances surrounding this case will be communicated 

to the DOL for further evaluation. 

Eight cases that previously had a PC greater than 50% would now have a PC less than 

50%. However, one of these claims would remain greater than 50% if the employee were 

determined to be a cobble cutter. The job title of this employee is listed as “unknown”. 

This report along with detailed information on the specific cases and calculations will be 

provided to the Department of Labor for determination of further action. 

5.0 References

1. ORAU Team (2003) Technical Basis Document: Basis for Development of an 

Exposure Matrix for Bethlehem Steel Corporation, ORAUT-TKBS-0001 Rev 00. 

2. ORAU Team (2004) Technical Basis Document: Basis for Development of an 

Exposure Matrix for Bethlehem Steel Corporation, ORAUT-TKBS-0001 Rev 01. 

3. OCAS (2006) Technical Basis Document: Basis for Development of an Exposure 

Matrix for Bethlehem Steel Corporation, OCAS-TKBS-0003 Rev 00. 

 
Office of Compensation Analysis and Support

Program Evaluation Report Document Number: OCAS-PER-007

Effective Date: (11/14/2006) Revision No. 0 Page 7 of 7 

Attachment 1